Lampreys are any jawless fish of the order Petromyzontiformes, placed in the superclass Cyclostomata. The adult lamprey may be characterized by a toothed, funnel-like sucking mouth.
Currently there are about 38 known species of lampreys. Parasitic species are the best known, and feed by boring into the flesh of other fish to suck their blood; but only 18 species of lampreys are parasitic. Adults of the non-parasitic species do not feed; they live off reserves acquired as ammocoetes (larvae), which they obtain through filter feeding.
Adults superficially resemble eels in that they have scaleless, elongated bodies, and can range from 13 to 100 cm (5 to 40 inches) in length. Lacking paired fins, adult lampreys have large eyes, one nostril on the top of the head, and seven gill pores on each side of the head. The pharynx is subdivided; the ventral part forming a respiratory tube that is isolated from the mouth by a valve called the velum.
This is an adaptation to how the adults feed, by preventing the prey’s body fluids from
escaping through the gills or interfering with gas exchange, which takes place by pumping water in and out of the gill pouches instead of taking it in through the mouth. Near the gills are the eyes, which are poorly developed and buried under skin in the larvae. The eyes complete their development during metamorphosis, and in adults are covered by a thin and transparent layer of skin that becomes opaque in preservatives.
The unique morphological characteristics of lampreys, such as their cartilaginous skeleton, suggest they are the sister taxon (see cladistics) of all living jawed vertebrates (gnathostomes), and are usually considered the most basal group of the Vertebrata. Instead of true vertebrae, they have a series of cartilaginous structures called arcualia arranged above the notochord. Hagfish, which resemble lampreys, have traditionally been considered the sister taxon of the true vertebrates (lampreys and gnathostomes) but DNA evidence suggests that they are in fact the sister taxon of lampreys.
Studies have shown that lampreys are amongst the most energy-efficient swimmers. Their swimming movements generate low-pressure zones around their body, which pull rather than push their bodies through the water.
Parasitic lampreys feed on prey as adults by attaching their mouthparts to the target animal’s body, then using their teeth to cut through surface tissues until they reach blood and body fluid. A study of stomach content of some lampreys have also shown remains of intestines, fins and vertebrae from their prey. Although attacks on humans do occur, they will generally not attack humans unless starved. Non-parasitic lampreys, which are usually freshwater species, do not feed as adults; they live off reserves acquired as ammocoetes (larvae), which they obtain through filter feeding.
Lampreys provide valuable insight into adaptive immune systems, as they possess a convergently evolved adaptive immunity with cells that function like the T cells and B cells seen in higher vertebrates. Lamprey leukocytes express surface variable lymphocyte receptors (VLRs) generated from somatic recombination of leucine-rich repeat gene segments in a recombination activating gene-independent manner.
Pouched lamprey (Geotria australis) larvae also have a very high tolerance for free iron in their bodies, and have well-developed biochemical systems for detoxification of the large quantities of these metal ions.
Adult lampreys spawn in rivers and then die. The young larvae, ammocoetes, spend several years in the rivers, where they live burrowed in fine sediment, filter feeding on detritus and microorganisms. Then, ammocoetes undergo a metamorphosis lasting several months.
Some species do not feed after metamorphosis, while others migrate to the sea or lakes, where they feed on different species of fish and even on marine mammals. Species whose adults migrate to the sea begin preying on other fish soon after metamorphosis, even as they begin swimming downstream.
Lampreys live mostly in coastal and fresh waters, although some species (e.g. Geotria australis, Petromyzon marinus, and Entosphenus tridentatus) travel significant distances in the open ocean, as evidenced by their lack of reproductive isolation between populations. Some species are found in land-locked lakes. They are found in most temperate regions except those in Africa. Their larvae (ammocoetes) have a low tolerance for high water temperatures, which may explain why they are not distributed in the tropics.
Sea lampreys have become a major pest in the North American Great Lakes. It is generally believed that they gained access to the lakes via canals during the early 20th century, but this theory is controversial. They are considered an invasive species, have no natural enemies in the lakes, and prey on many species of commercial value, such as lake trout.
Lampreys are now found mostly in the streams that feed the lakes, and controlled with special barriers to prevent the upstream movement of adults, or by the application of toxicants called lampricides, which are harmless to most other aquatic species; however, those programs are complicated and expensive, and do not eradicate the lampreys from the lakes, but merely keep them in check.
Grimpoteuthis spp, are known as the deepest living of all octopus species. They live on the seafloor or hover just slightly above it at depths of depths of 3000 to 4000 m (9800 to 13000 ft).
The similarity of the ear-like fins protruding from the top of the mantle of the Dumbo octopus to the ears of the Disney character, Dumbo, the Flying elephant, led to the common name, dumbo. There are about 17 species of Dumbo octopus that belong to a group called “umbrella octopus,” because they are able to float with an umbrella-like look to their mantle. While these species can “flush” color as do more shallow species, their mouth structure is different. It has a degenerated radula-type opening that allows it to swallow prey whole instead of having to tear and grind it. This feeding characteristic unique to the genus Grimpoteuthis.
Grimpoteuthis spp, known as the deepest living of all octopus species, live on the bottom, or hovering just slightly above the seafloor at depths of depths of 3000 to 4000 m (9800 to 13000 ft), with some living as deep as 7,000 m (23000 ft) below sea level.
Dumbo octopus have a semi-translucent body with an internal “U” or “V” cartilaginous shell or mantle, which gives them some shape. Some Dumbos are short, squat and yellow, while others resemble a sea jelly with one giant, brown, walking shoe. Some have suckers, in addition to spines, on all of their webbed tentacles while others look more like a traditional octopus with the addition of blue or other colored “ears.” Prominent ear-like fins protrude from the mantle just above the almost sightless eyes of the octopus. They have eight webbed tentacles.
Most species are 20-30 cm (7.9-12 in) length. The largest Dumbo octopus was 1.8 m (6 ft 32in) length and weighed in 5.9 kg (13 lb)
Dumbo octopuses pounce on prey and eat it whole. Their diet includes copepods, isopods, bristle worms, and amphipods. Much of the food they consume is also found around ocean vent ecosystems or floating along in the current.
All species of Grimpoteuthis are bathyal creatures, living at extreme depths of 3,000 to 4,000 metres (9,800 to 13,100 ft) with some living up to 7,000 metres (23,000 ft) below sea level, which is the deepest of any known octopus. They are some of the rarest of the Octopoda species. They have been found worldwide in the waters of New Zealand, Australia, Monterey Bay, Oregon, Philippines, Martha’s Vineyard, Papua New Guinea and Azores. They can flush the transparent layer of their skin at will, and are pelagic animals, as with all other cirrate octopuses. The largest Dumbo octopus ever recorded was 1.8 metres (5.9 ft) in length and weighed 5.9 kilograms (13 lb). The average size for most species is 20–30 centimetres (7.9–12 in) in length. The average weight is still undetermined.
Species of Grimpoteuthis face few direct threats from humans, living at depths below 3,000 metres (9,800 ft). Natural predators include sharks, killer whales, tuna and predatory cephalopods.
The genus has a distinct habit of swimming. They flap their ear-like fins to propel themselves upwards. Movement of the arms can be used to help the animal move in any direction. The arms permit the animal to crawl along the seafloor, to capture prey, lay eggs, explore, etc. Dumbos hover above the sea floor, searching for polychaete worms, pelagic copepods, isopods, amphipods, and other crustaceans for food. Prey is captured by pouncing on the target, which then is swallowed whole.
Females have no distinct period for breeding. Females carry multiple eggs in various stages of maturation, suggesting that they have no optimal breeding period. Male octopuses have a separate protuberance on one of their arms that carries an encapsulated sperm packet to the female. It is hypothesized that the female can then distribute this sperm to the eggs at any given time based on environmental conditions. The females lay the eggs under small rocks or on shells in the deep ocean or can even carry them on her arms, by tucking the eggs behind the wide webbing, until she finds a safe place that would provide them with the best fitness. As with other octopuses, females do not invest any further time in the young after they hatch because once they are born they are able to defend themselves.
The maned wolf (Chrysocyon brachyurus) is the largest canid of South America. Its markings resemble those of foxes, but it is not a fox, nor is it a wolf, as it is not closely related to other canids. It is the only species in the genus Chrysocyon (meaning “golden dog”).
This mammal is found in open and semi-open habitats, especially grasslands with scattered bushes and trees, in south, central-west, and southeastern Brazil, Paraguay, northern Argentina, Bolivia east and north of the Andes, and far southeastern Peru (Pampas del Heath only).It is very rare in Uruguay, possibly being displaced completely through loss of habitat. IUCN lists it as near threatened, while it is considered a vulnerable species by the Brazilian government (IBAMA).
is known locally as aguará guazú (meaning “large fox” in the Guarani language), or “kalak” by the Toba, lobo de crin, lobo de los esteros, or lobo colorado, and as lobo-guará in Brazil. It also is called borochi in Bolivia.
The maned wolf bears minor similarities to the red fox, although it belongs to a different genus. The average adult weighs 23 kg (51 lb) and stands 90 cm (35 in) tall at the shoulder, has a head-body length of 100 cm (39 in) with the tail adding another 45 cm (18 in). Its ears are large and long (7 inches).
The maned wolf is the tallest of the wild canids; its long legs are likely an adaptation to the tall grasslands of its native habitat. Fur of the maned wolf may be reddish brown to golden orange on the sides with long, black legs, and a distinctive black mane. The coat is marked further with a whitish tuft at the tip of the tail and a white “bib” beneath the throat. The mane is erectile, and typically, is used to enlarge the wolf’s profile when threatened or when displaying aggression. Rare melanistic maned wolves exist, and the first black adult maned wolf was photographed by camera trap in northern Minas Gerais in Brazil in 2013.
The maned wolf also is known for the distinctive odor of its territory markings, which has earned it the nickname “skunk wolf.”
Unlike other large canids (such as the gray wolf, the African hunting dog, or the dhole) the maned wolf does not form packs. It hunts alone, usually between sundown and midnight. Maned wolves rotate their large ears to listen for prey animals in the grass. They tap the ground with a front foot to flush out the prey and pounce to catch it. It kills its prey by biting on the neck or back, and shaking the prey violently if necessary. Monogamous pairs may defend a shared territory of approximately 30 km2 (12 sq mi), although outside of mating, the individuals may meet seldom. The territory is crisscrossed by paths that the maned wolves create as they patrol at night. Several adults may congregate in the presence of a plentiful food source, for example, a fire-cleared patch of grassland that would leave small vertebrate prey exposed while foraging.
Both female and male maned wolves use their urine to communicate, e.g. to mark their hunting paths or the places where they have buried hunted prey. The urine has a very distinctive odor, which some people liken to hops or cannabis. The responsible substance very likely is a pyrazine, which also occurs in both plants. (At the Rotterdam Zoo, this smell once set the police on a hunt for cannabis smokers.) The preferred habitat of the maned wolf include grasslands, scrub prairies, and forests.
Their mating season ranges from November to April. Gestation lasts 60 to 65 days and a litter may have from two to six black-furred pups, each weighing approximately 450 g (16 oz). Pups are fully grown when one year old. During that first year, the pups are known to rely on their parents for food.
The maned wolf is omnivorous. It specialises in preying on small and medium-sized animals, including small mammals (typically rodents and rabbits), birds, and even fish, but a large portion of its diet (more than 50%, according to some studies) is vegetable matter, including sugarcane, tubers, and fruit (especially the wolf apple, Solanum lycocarpum, a tomato-like fruit). Traditionally, captive maned wolves were fed meat-heavy diets, but that caused them to develop bladder stones. Zoo diets for them now feature fruits and vegetables, as well as meat and dog chow.
The maned wolf participates in symbiotic relationships. It contributes to the propagation and dissemination of the plants that it feeds on, through excretion. Often maned wolves defecate on the nests of leafcutter ants. The ants then use the dung to fertilize their fungus gardens, but they discard the seeds contained in the dung onto refuse piles just outside their nests. This process significantly increases the germination rate of the seeds.
The maned wolf is not a common prey species for any predator, although it may be attacked or killed by feral dogs. An additional threat to the maned wolf exists from sharing territory with domestic dogs. The maned wolf is particularly susceptible to infection by the giant kidney worm, a potentially fatal parasite that also may infect domestic dogs.
Generally, the maned wolf is shy and flees when alarmed, so it poses little direct threat to humans. Popularly, the maned wolf is thought to have the potential of being a chicken thief. It once was considered a similar threat to cattle and sheep, although this now is known to be false.
Historically, in a few parts of Brazil, these animals were hunted down for some body parts, notably the eyes, that were believed to be good luck charms. Since its classification as a vulnerable species by the Brazilian government, it has received greater consideration and protection.
They are threatened by habitat loss and being run over by automobiles. Feral and domestic dogs pass on diseases to them, and have been known to attack them.
The species occurs in several protected areas, including the national parks of Caraça and Emas in Brazil. The maned wolf is well represented in captivity and has been bred successfully at many zoos, particularly in Argentina, North America (part of a Species Survival Plan) and Europe (part of a European Endangered Species Programme). The Smithsonian National Zoo Park has been working to protect maned wolves for nearly 30 years and coordinates the collaborative, inter-zoo maned wolf Species Survival Plan of North America, which includes breeding maned wolves, studying them in the wild, protecting their habitat, and educating people about them.
Meet the Tarsier
Tarsiers have enormous eyes and long feet. Their feet have extremely elongated tarsus bones, which is how they got their name. They are primarily insectivorous, and catch insects by jumping at them. They are also known to prey on birds and snakes. As they jump from tree to tree, tarsiers can catch even birds in motion.
Gestation takes about six months, and tarsiers give birth to single offspring. All tarsier species are nocturnal in their habits, but like many nocturnal
organisms some individuals may show
more or less activity during the daytime.
Anatomy and Physiology
Tarsiers are small animals with enormous eyes; each eyeball is approximately 16 mm in diameter and is as large as its entire brain. The unique cranial anatomy of the tarsier results from the need to balance their large eyes and heavy head so they are able to wait silently for nutritious prey. Tarsiers have an incredibly strong auditory sense because their auditory cortex is very distinct. Tarsiers also have very long hind limbs, due mostly to the extremely elongated tarsus bones of the feet, from which the animals get their name. The combination of their elongated tarsi and fused tibiofibulae makes them morphologically specialized for vertical clinging and leaping. The head and body range from 10 to 15 cm in length, but the hind limbs are about twice this long (including the feet), and they also have a slender tail from 20 to 25 cm long. Their fingers are also elongated, with the third finger being about the same length as the upper arm. Most of the digits have nails, but the second and third toes of the hind feet bear claws instead, which are used for grooming. Tarsiers have very soft, velvety fur, which is generally buff, beige, or ochre in color. Unlike other prosimians, tarsiers lack any toothcomb.
Unlike many nocturnal vertebrates, tarsiers lack a light-reflecting area (tapetum lucidum) of the eye and have a fovea.
The tarsier’s brain is different from other primates in terms of the arrangement of the connections between the two eyes and the lateral geniculate nucleus, which is the main region of the thalamus that receives visual information. The sequence of cellular layers receiving information from the ipsilateral (same side of the head) and contralateral (opposite side of the head) eyes in the lateral geniculate nucleus distinguishes tarsiers from lemurs, lorises, and monkeys, which are all similar in this respect. Some neuroscientists suggested that “this apparent difference distinguishes tarsiers from all other primates, reinforcing the view that they arose in an early, independent line of primate evolution.”
Philippine tarsiers are capable of hearing frequencies as high as 91 kHz. They are also capable of vocalizations with a dominant frequency of 70 kHz.
Tarsiers are the only extant entirely carnivorous primates: they are primarily insectivorous, and catch insects by jumping at them. They are also known to prey on birds, snakes, lizards, and bats.
Pygmy tarsiers differ from other species in terms of their morphology, communication, and behavior. The differences in morphology that distinguish pygmy tarsiers from other species are likely based on their high altitude environment.
All tarsier species are nocturnal in their habits, but like many nocturnal organisms, some individuals may show more or less activity during the daytime. Based on the anatomy of all tarsiers, they are all adapted for leaping even though they all vary based on their species.
Ecological variation is responsible for differences in morphology and behavior in tarsiers because different species become adapted to local conditions based on the level of altitude. For example, the colder climate at higher elevations can influence cranial morphology.
Gestation takes about six months, and tarsiers give birth to single offspring. Young tarsiers are born furred, and with open eyes, and are able to climb within a day of birth. They reach sexual maturity by the end of their second year. Sociality and mating systems vary, with tarsiers from Sulawesi living in small family groups, while Philippine and western tarsiers are reported to sleep and forage alone.
Tarsiers tend to be extremely shy animals.
Tarsiers have never formed successful breeding colonies in captivity. This may be partly due to their special feeding requirements.
A sanctuary near the town of Corella, on the Philippine island of Bohol, is having some success restoring tarsier populations. The Philippines Tarsier Foundation (PTFI) has developed a large, semi-wild enclosure known as the Tarsier Research and Development Center. Carlito Pizarras, also known as the “Tarsier Man”, founded this sanctuary where visitors can observe tarsiers in the wild. As of 2011, the sanctuary was maintained by him and his brother. The trees in the sanctuary are populated with nocturnal insects that make up the tarsier’s diet.
The conservation status of all tarsiers is vulnerable to extinction. Tarsiers are a conservation dependent species, meaning that they need to have more and improved management of protected habitats or they will definitely become extinct in the future.
The 2008-described Siau Island tarsier is regarded as Critically Endangered and was listed among The World’s 25 Most Endangered Primates by Conservation International and the IUCN/SCC Primate Specialist Group in 2008. The Malaysian government protects tarsiers by listing them in the Totally Protected Animals of Sarawak, the Malaysian state in Borneo where they are commonly found.
A new scheme to conserve the tarsiers of Mount Matutum near Tupi in South Cotabato on the island of Mindanao is being organized by the Tupi civil government and the charity Endangered Species International (ESI). Tarsier UK is also involved on the margins helping the Tupi Government to educate the children of Tupi about the importance of the animal. ESI are hoping to build a visitor center on the slopes of Mount Matutum and help the local indigenous peoples to farm more environmentally and look after the tarsiers. The first stage in this is educating the local peoples on the importance of keeping the animal safe and secure. A number of native tarsier friendly trees have been replanted on land which had been cleared previously for fruit tree and coconut tree planting.
The pink fairy armadillo is the smallest species of armadillo (mammals of the families Chlamyphoridae and Dasypodidae, recognized by a bony armor shell). This desert-adapted animal is endemic to central Argentina and can be found inhabiting sandy plains, dunes, and scrubby grasslands.
Pink fairy armadillos have small eyes, silky yellowish white fur, and a flexible dorsal shell that is solely attached to its body by a thin dorsal membrane. In addition, its spatula-shaped tail protrudes from a vertical plate at the blunt rear of its shell. This creature exhibits nocturnal and solitary habits and has a diet that is mainly composed of insects, worms, snails, and various plant parts.
The conservation status for pink fairy armadillo is still uncertain, and it is listed as Data Deficient by the IUCN Red List of Threatened Species. The decline in population for this species has generally been attributed to farming activities and predators including domestic dogs and cats. Pink fairy armadillos are found less commonly than they were a few decades ago, and the field sightings have been rare and incidental. Individuals that have been caught in the wild had a tendency to die during or a couple days after they were transported from their natural habitat to captive facilities.
Pink fairy armadillos are nocturnal burrowing mammals endemic to the xeric environment in central Argentina. They have been found south of Mendoza province as well as north of Rio Negro and south of Buenos Aires.
The pink fairy armadillo is classified as a fossorial generalist insectivore. Their main source of food consists of ants and larvae it finds underground. While those are its primary sources of food, the armadillos are known to eat worms, snails, and other insects. If these insects and invertebrates can’t be found plant leaves and roots make a good secondary dietary option for their underground lifestyle.
The armadillo has two massive sets of claws on its front and hind limbs help it to dig the burrows in compacted soil very quickly. The pink fairy armadillo is nicknamed the “sand-swimmer” because it is said that it can “burrow through the ground as fast as a fish can swim in the sea.” These claws are very big relatively to the size of this animal which makes it difficult for it to walk on a hard surface.